Help with Vems idle issue and cold start (logs)

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Re: Help with Vems idle issue and cold start (logs)

Postby ChrisAudi80 » Sun Nov 11, 2018 11:28 pm

morris400 wrote:
ChrisAudi80 wrote:Try this.


Will give this a shot for sure! You set the crank pulse to 0.0, why was that?


It's what I use. Also changed the number of cycles for afterstart.

You had 8.0ms of primepulse and no downscaling for temp. That means you were probably flooding the engine, hot or cold start.
You always inject 8.0ms in addition to cranking, afterstart and warm up enrichment. Way too much.
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Re: Help with Vems idle issue and cold start (logs)

Postby morris400 » Tue Dec 11, 2018 8:07 pm

gave the new file a go, and same issues. 3 starts and only the 3rd one mainatined idle. Thinking maybe the afters start enrichment? had the car out for a nice long drive, about 30 mins and another 10 mins of messing with the idle. ive attached my current config, my log file fromm today is to big . my main concern is no matter what RPM, when i stomp on the gas, it will lean out for a split second then lambda goes normal. is this normal?

the one thing i want to do is brake boost to hold a certin RPM while boost builds, weather is the trick right now. its pretty cold and i only have summer tires. im going to try some some more tuning this week.

thanks guys.
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kenny #15, changed idle and ego settings.vemscfg
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Re: Help with Vems idle issue and cold start (logs)

Postby morris400 » Wed Dec 12, 2018 5:01 pm

Looking to see if I can get pointed in the right direction with the afterstart and warmup enrichments. The cranking indictment seems good cause it fires up fine, it just dies after 2-4 seconds. And during the warmup..if I blip the throttle with out allowing it to idle for a few mins first causing the car to stall. Thinking more enrichment would help?
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Re: Help with Vems idle issue and cold start (logs)

Postby ChrisAudi80 » Sun Dec 16, 2018 8:27 pm

morris400 wrote:gave the new file a go, and same issues. 3 starts and only the 3rd one mainatined idle. Thinking maybe the afters start enrichment? had the car out for a nice long drive, about 30 mins and another 10 mins of messing with the idle. ive attached my current config, my log file fromm today is to big . my main concern is no matter what RPM, when i stomp on the gas, it will lean out for a split second then lambda goes normal. is this normal?

the one thing i want to do is brake boost to hold a certin RPM while boost builds, weather is the trick right now. its pretty cold and i only have summer tires. im going to try some some more tuning this week.

thanks guys.


That lean peak is partially Accell Enr and incorrect injector ramp up. Looked through your config and noticed you changed strategy to simplified.
I changed that back to traditional with my injector settings, which work well for me. You changed afterstart cycles to only 16. That might be why it does not maintain idle. The stall on throttle off, might be not enough timing below the idle RPM. I have added 3 degrees to "catch" it at 700.

If you could make a log of about 10-15 minutes it would help. Letting it idle to get to about 50C coolant and then drive. An easy drive. No flooring!
In order to tune AE, you need to just press the throttle and hold it for 5 secs or more. That way the fuel stabilizes. Not on/off. Try small to medium throttle changes at idle, 2000, 3500rpm.

I have made some edits. You said my AE settings before did not work. Was it too rich or lean? Anyway, try this again.
Attachments
kenny #15 changed idle and ego settings V2.vemscfg
(12.97 KiB) Downloaded 2 times
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Re: Help with Vems idle issue and cold start (logs)

Postby morris400 » Mon Dec 17, 2018 4:12 pm

Hey Chris, hope thge holidays are treating you well.

i laugh at your post only cause you keep saying no flooring! lol. i agree, the only reason i do is to see if i keep getting that spike. for every drive i do, im crusing around at 60km/h with a merge on and off the hwy. i will say im overall happy with the VE table while crusing. maintains the requested lambda non stop. thats with ego off as well. during the warm up its rich, but after that its .95-1.0.

today i changed my crank EN and afterstart EN, was able to get the car to start on the second start super easy. so i do think im heading in the right direction there.

i will add more afterstart cycles, totally makes sence that it should help.

id say right now my only issue is that lean peak, and its only on quick accelertion. if i slowly increase boost it will peak at the req boost (no over boost ) and it wont spkie lean. its only when i mash the pedal that it spikes the comes back down to normal with in .2 of a second. ill use your Accel EN settings to try and correct this. would the billet comp wheel be the issue here? maybe it just spikes too quick?

i raised the EGO temp to 70 like you said, i ran into some issues with this today at idle after my run. EGO would come on and off at idle causing really rich idle. it would go from .81 to 1.0 at idle with the RPM at 900-970.

FYI, what i do is take your suggestions and plug them into my config file and rename it 15.1 or 15.2 ect for my
own record keeping. i make 1 or 2 changes per time so i know whqt the changes effect rather thenh making a bunch of changes all at once.
Attachments
Log from 15.4.vemslog
(2.9 MiB) Downloaded 1 time
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Re: Help with Vems idle issue and cold start (logs)

Postby ChrisAudi80 » Tue Dec 18, 2018 1:03 am

morris400 wrote:Hey Chris, hope thge holidays are treating you well.

i laugh at your post only cause you keep saying no flooring! lol. i agree, the only reason i do is to see if i keep getting that spike. for every drive i do, im crusing around at 60km/h with a merge on and off the hwy. i will say im overall happy with the VE table while crusing. maintains the requested lambda non stop. thats with ego off as well. during the warm up its rich, but after that its .95-1.0.

today i changed my crank EN and afterstart EN, was able to get the car to start on the second start super easy. so i do think im heading in the right direction there.

i will add more afterstart cycles, totally makes sence that it should help.

id say right now my only issue is that lean peak, and its only on quick accelertion. if i slowly increase boost it will peak at the req boost (no over boost ) and it wont spkie lean. its only when i mash the pedal that it spikes the comes back down to normal with in .2 of a second. ill use your Accel EN settings to try and correct this. would the billet comp wheel be the issue here? maybe it just spikes too quick?

i raised the EGO temp to 70 like you said, i ran into some issues with this today at idle after my run. EGO would come on and off at idle causing really rich idle. it would go from .81 to 1.0 at idle with the RPM at 900-970.

FYI, what i do is take your suggestions and plug them into my config file and rename it 15.1 or 15.2 ect for my
own record keeping. i make 1 or 2 changes per time so i know whqt the changes effect rather thenh making a bunch of changes all at once.


That lean peak has nothing to do with your compressor wheel. It is just injector and AE settings. Your AE settings don't go high enough. Highest dTPS you have is 26, while when you mash it, it shows 66! That is why you go crazy lean! See pictures.
Another reason you have lean peaks on accel is because EGO is pulling a lot of fuel. It is canceled on throttle input, but it does have an effect.

I hate to say this, but your VE table needs a lot of work. You say it maintains target lambda with EGO on or off. Why does the log then show EGO correction 85%? I can see in the log with my settings that it pulls fuel almost everywhere. EGO correction should be 100% if on target. Another thing is that you reach very low IPW. Just 1.4-1.5ms. The Dekas are not really linear that low. They start to go unstable at 1.7ms I have noticed. That is why you have that weird oscillation in lambda and MAP between time mark 11.30 and 12.20, I think.

Is your thermostat new? Coolant never goes above 87C. I recommend you get a stock 87C 'stat.
I see the on/off EGO issue at the end. That is odd, but not because of the higher enable temp. That is something else.
Attachments
Kenny log pic 2 EGO corr.jpg
Kenny log pic 2 EGO corr.jpg (297.15 KiB) Viewed 30 times
Kenny log pic 1.jpg
Kenny log pic 1.jpg (292.35 KiB) Viewed 30 times
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Re: Help with Vems idle issue and cold start (logs)

Postby ChrisAudi80 » Tue Dec 18, 2018 8:14 am

Something else.

I think it would be better if you rescale the VE table RPM at least. You have no resolution at cruise RPM.
Try scaling from 700 to 7000 for now and 30kpa to 260kpa. Same with the timing table. That way you get a better idea of what is happening.
If you have a row for every 10kpa upto 102, then in steps of 20kpa, it would be very useful.

You also need more AE. For sure. You WILL melt a piston if you keep going like this. The lean condition is quite long actually.

You are too rich in vacuum and too lean in boost. See attached config to get an idea of what I mean. You don't have to use it, but I do recommend it.
Understand you only want to change few things at a time, but these are quite essential changes. You are on pump gas, not E85.
Attachments
kenny #15 4 ver2.vemscfg
(12.97 KiB) Downloaded 1 time
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Re: Help with Vems idle issue and cold start (logs)

Postby morris400 » Tue Dec 18, 2018 10:01 am

Hey Chris,

I agree on everything you mentioned above. I was unsure how bad the lean condition was as it seemed really quick to me. As you can see in the log it's a split second, but obviously it's not good.

I'll load that 15.4 config as per the changes you made. The VE table looks really rich up high but I have less experience here so I trust you.

I have since added Acell EN on another config but not ran it yet. Pretty much everything you mentioned yesterday was after that log I posted. I made the cahanges but not tested. Like i said, I'd like to test this VE table so i will load your config as per.

I'll report back later with a log and my results.
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Re: Help with Vems idle issue and cold start (logs)

Postby ChrisAudi80 » Tue Dec 18, 2018 11:13 am

Sounds like a plan. Go easy at first.

Try to cover as much of the vacuum area as possible. Like slowly climbing in the revs in second gear and third. If you can cover the same rev range with two different MAP rows, it can really help predict the upper table. After that, low boost along the MAP rows. Then we have the third and fourth points. The table is not completely linear, of course. There is a changeover where it curves sharply in low vacuum. Say below 40 or so. Small dip around idle, but not too steep. What you might find is a very slight dip in the mid range. I've seen this in a few maps besides mine.

Speaking of steep, your ignition timing changes were very sudden. 10 degrees in 500 rpm. Should not really be more than 5. The table is more conservative now, but not badly. Pump gas, remember.

If it goes too rich in boost, it is not as bad as very lean. 1.2 @ 245kpa is not good.

I'm temped to give you my VE map and see what happens...

Also, a fuel pressure sensor would be good idea at this point. It has helped me understand better what's happening. If you see some weird shit happening like oscillations or sudden drops, you can save the engine too.
A decent 100psi sensor is like $150. Make sure it comes with a calibration cert. Wire it in to one of the open analog in channels. You will have to check how to do that on your PnP. There is a tutorial on the VEMS YT channel on how to configure that.
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Re: Help with Vems idle issue and cold start (logs)

Postby morris400 » Tue Dec 18, 2018 12:06 pm

for the thermostat, yes its new. the 87c is normal for my car, also remember were dealing with temps here right now of -10c as well. in the dead of summer here id expect to see that number higher for sure. but its brand new and its correct as the one i pulled out was not correct lol.

with the EGO correct not matching the current VE... what could be this cause? i see its off by about 10%. where should i look to solve this issue?

with the EGO on/off issue, it only started when i raised the temp from 26c to 60c. ill review other logs as well to see if the issue was there... but this was the first time i recall this issue
1994 UrS4 Intended Acceleration Chip
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Re: Help with Vems idle issue and cold start (logs)

Postby morris400 » Tue Dec 18, 2018 7:57 pm

Quick update. So I ran my file # 16 in which I only changed crank en, afterstart en, and accel en. And bam...fire up on 1st start. Let it idle warm and played around a bit with the idle VE znd it seems that lower the VE to 54/49 works perfect.

With the acceleration set the way you had it at 100% for the RPM enrich did not work at idle. Every time I did a quick blip the rpm would drop to 500 and go super rich (.70) then come back. So I dropped the accel en at 1000/3000 rpm from 100 to 30% and perfect. No bog and no stall.

I've not had a chance to drive it yet but will tomorrow morning and see it the accell en kills the lean spike. I have good feelings .

Chris, for your VE adjustment. I'm going to wait and see how the car drive before I use your VE table, I'm concerned it's really rich I'm watching my log now and what I'm seeing on between current VE and ego corrected VE is that my VE table is already really rich when crusing . 5-10% almost everywhere. When I hit boost it's when it goes stupid lean although the current VE reads 106% and corrected reads 144%.
1994 UrS4 Intended Acceleration Chip
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Re: Help with Vems idle issue and cold start (logs)

Postby ChrisAudi80 » Tue Dec 18, 2018 10:06 pm

morris400 wrote:Quick update. So I ran my file # 16 in which I only changed crank en, afterstart en, and accel en. And bam...fire up on 1st start. Let it idle warm and played around a bit with the idle VE znd it seems that lower the VE to 54/49 works perfect.

With the acceleration set the way you had it at 100% for the RPM enrich did not work at idle. Every time I did a quick blip the rpm would drop to 500 and go super rich (.70) then come back. So I dropped the accel en at 1000/3000 rpm from 100 to 30% and perfect. No bog and no stall.

I've not had a chance to drive it yet but will tomorrow morning and see it the accell en kills the lean spike. I have good feelings .

Chris, for your VE adjustment. I'm going to wait and see how the car drive before I use your VE table, I'm concerned it's really rich I'm watching my log now and what I'm seeing on between current VE and ego corrected VE is that my VE table is already really rich when crusing . 5-10% almost everywhere. When I hit boost it's when it goes stupid lean although the current VE reads 106% and corrected reads 144%.


Well, that is it! Current VE is what you have in the table, but the ECU says you need 144 in order to hit the requested lambda target. If corrected VE asks for 144, put that in. Then try again. EGO control tells you what you should aim for. It's not always spot on, but you get close.

The idea is to hold in certain cells so that fuel requirement stabilizes. Any sharp transitions cannot give good information for tuning.

That is why dyno-tuning is so much faster. You can hold the engine in the cells you want. It brakes down the car by applying load so opening the throttle further to go up the MAP axis at one RPM column. You do something like this with brake boosting. I cannot do that here because of traffic.
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